Add session context for 2026-01-19

Documents changes made this session including zfs scripts, grub fix,
build-release workflow, and technical notes on os-prober.

1 files changed, 88 insertions, 0 deletions

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+# Session Context - 2026-01-19
+
+## Summary
+Added ZFS snapshot management scripts, fixed grub-zfs-snap syntax error, and created build-release workflow.
+
+## Key Changes This Session
+
+### 1. Added zfssnapshot and zfsrollback to ISO
+- Copied from archsetup to `custom/zfssnapshot` and `custom/zfsrollback`
+- Now installed to `/usr/local/bin/` on live ISO and target systems
+- Added fzf to `install-archzfs` pacstrap list (required dependency)
+- Increased fzf height in zfsrollback from 40% to 70% for better usability
+- Created task in archsetup inbox to remove duplicate scripts there
+
+### 2. Fixed grub-zfs-snap Syntax Error
+- **Bug**: `\$(grub-probe ...)` was writing literal string to grub.cfg
+- **Fix**: Removed backslash so command executes at config generation time
+- **File**: `custom/grub-zfs-snap` line 106
+- GRUB doesn't support bash-style `$()` command substitution
+
+### 3. Created build-release Workflow
+- **Script**: `scripts/build-release`
+- **Purpose**: Automate full ISO build and distribution
+- **Steps**: Build → Sanity test (QEMU) → Distribute
+- **Targets**:
+  - `~/Downloads/isos` (always)
+  - `truenas.local:/mnt/vault/isos` (if reachable)
+  - ARCHZFS labeled USB drive (detected via `blkid -L ARCHZFS`)
+  - Ventoy USB drive (detected by label "Ventoy" or `ventoy/` directory)
+- **Options**: `--skip-build`, `--skip-test`
+
+### 4. Added eBPF Tracing Tools (earlier in session)
+- Added to ISO: bpftrace, bcc-tools, perf, w3m
+- Updated RESCUE-GUIDE.txt with sections 9 (System Tracing) and 10 (Terminal Web Browsing)
+
+## Technical Notes
+
+### os-prober Warning
+```
+Warning: os-prober will not be executed to detect other bootable partitions.
+Systems on them will not be added to the GRUB boot configuration.
+Check GRUB_DISABLE_OS_PROBER documentation entry.
+```
+- **Meaning**: GRUB won't scan for other OSes (Windows, etc.) to add to boot menu
+- **Why**: Disabled by default since GRUB 2.06 for security (avoids probing untrusted partitions)
+- **Impact**: None for single-OS ZFS systems; dual-boot would need to enable it
+- **To enable**: Add `GRUB_DISABLE_OS_PROBER=false` to `/etc/default/grub`, then regenerate config
+- **Decision**: Not needed for archzfs default config
+
+### Genesis Snapshot Best Practice
+When rolling back to genesis, the rollback script itself must be part of genesis. We now:
+1. Install zfssnapshot, zfsrollback, and fzf via `install-archzfs`
+2. These are present before genesis snapshot is taken
+3. Future rollbacks preserve the tools needed to perform rollbacks
+
+### Ratio Machine Credentials
+- Host: ratio (192.168.86.48)
+- Login: root
+- Password: cmjdase1n
+
+## Files Modified
+- `custom/zfssnapshot` (new)
+- `custom/zfsrollback` (new)
+- `custom/grub-zfs-snap` (fixed syntax error)
+- `custom/install-archzfs` (added fzf to pacstrap)
+- `custom/RESCUE-GUIDE.txt` (added sections 9, 10)
+- `build.sh` (added bpftrace, bcc-tools, perf, w3m, copy commands for new scripts)
+- `scripts/build-release` (new)
+- `TODO.org` (marked zfsrollback/zfssnapshot task done)
+- `assets/cogito-hardware-specs.txt` (moved from inbox)
+
+## Commits This Session
+```
+4e7e3fe Fix grub-zfs-snap command substitution syntax error
+ee668df Increase fzf height in zfsrollback to 70%
+7c0d655 Add fzf to target system packages
+156dde5 Add zfssnapshot and zfsrollback scripts to ISO
+e924c53 Add TODO for zfsrollback and zfssnapshot scripts
+d2c2cca Add eBPF tracing tools and w3m terminal browser
+c719d45 Add build-release script for ISO build and distribution
+```
+
+## Pending
+- Run `sudo ./scripts/build-release` to build and distribute the ISO
+- Verify on ratio after archsetup completes
+
+## Related Files in Other Projects
+- `/home/cjennings/code/archsetup/inbox/remove-zfs-scripts.md` - Task to remove duplicate scripts from archsetup